Brahma Sutras
ॐ आर्त्विज्यमित्यौडुलोमिः तस्मै हि परिक्रियते ॐ ॥ ३-४-४५॥
The (teacher) Audulomi says that it is the duty of the priest (to undertake such meditations), for he is retained for that.
english translation
OM ArtvijyamityauDulomiH tasmai hi parikriyate OM ॥ 3-4-45॥
hk transliteration by Sanscript